/*
 * jQuery UI Accordion
 * 
 * Copyright (c) 2007, 2008 Jörn Zaefferer
 * Dual licensed under the MIT (MIT-LICENSE.txt)
 * and GPL (GPL-LICENSE.txt) licenses.
 *
 * http://docs.jquery.com/UI/Accordion
 *
 * Depends:
 *	ui.core.js
 *
 * Revision: $Id: ui.accordion.js 5452 2008-05-05 16:42:08Z rdworth $
 */

;(function($) {

	$.widget("ui.accordion", {
		init: function() {
			var options = this.options;
			
			if ( options.navigation ) {
				var current = this.element.find("a").filter(options.navigationFilter);
				if ( current.length ) {
					if ( current.filter(options.header).length ) {
						options.active = current;
					} else {
						options.active = current.parent().parent().prev();
						current.addClass("current");
					}
				}
			}
			
			// calculate active if not specified, using the first header
			options.headers = this.element.find(options.header);
			options.active = findActive(options.headers, options.active);
			
			if (!this.element.hasClass("ui-accordion")) {
				this.element.addClass("ui-accordion");
				$("<span class='ui-accordion-left'/>").insertBefore(options.headers);
				$("<span class='ui-accordion-right'/>").appendTo(options.headers);
				options.headers.addClass("ui-accordion-header").attr("tabindex", "0");
			}
			
			var maxHeight;
			if ( options.fillSpace ) {
				maxHeight = this.element.parent().height();
				options.headers.each(function() {
					maxHeight -= $(this).outerHeight();
				});
				var maxPadding = 0;
				options.headers.next().each(function() {
					maxPadding = Math.max(maxPadding, $(this).innerHeight() - $(this).height());
				}).height(maxHeight - maxPadding);
			} else if ( options.autoHeight ) {
				maxHeight = 0;
				options.headers.next().each(function() {
					maxHeight = Math.max(maxHeight, $(this).outerHeight());
				}).height(maxHeight);
			}
		
			options.headers
				.not(options.active || "")
				.next()
				.hide();
			options.active.parent().andSelf().addClass(options.selectedClass);
			
			if (options.event) {
				this.element.bind((options.event) + ".accordion", clickHandler);
			}
		},
		activate: function(index) {
			// call clickHandler with custom event
			clickHandler.call(this.element[0], {
				target: findActive( this.options.headers, index )[0]
			});
		},
		destroy: function() {
			this.options.headers.next().css("display", "");
			if ( this.options.fillSpace || this.options.autoHeight ) {
				this.options.headers.next().css("height", "");
			}
			$.removeData(this.element[0], "accordion");
			this.element.removeClass("ui-accordion").unbind(".accordion");
		}
	});
	
	function scopeCallback(callback, scope) {
		return function() {
			return callback.apply(scope, arguments);
		};
	};
	
	function completed(cancel) {
		// if removed while animated data can be empty
		if (!$.data(this, "accordion")) {
			return;
		}
		
		var instance = $.data(this, "accordion");
		var options = instance.options;
		options.running = cancel ? 0 : --options.running;
		if ( options.running ) {
			return;
		}
		if ( options.clearStyle ) {
			options.toShow.add(options.toHide).css({
				height: "",
				overflow: ""
			});
		}
		$(this).triggerHandler("accordionchange", [options.data], options.change);
	}
	
	function toggle(toShow, toHide, data, clickedActive, down) {
		var options = $.data(this, "accordion").options;
		options.toShow = toShow;
		options.toHide = toHide;
		options.data = data;
		var complete = scopeCallback(completed, this);
		
		// count elements to animate
		options.running = toHide.size() === 0 ? toShow.size() : toHide.size();
		
		if ( options.animated ) {
			if ( !options.alwaysOpen && clickedActive ) {
				$.ui.accordion.animations[options.animated]({
					toShow: jQuery([]),
					toHide: toHide,
					complete: complete,
					down: down,
					autoHeight: options.autoHeight
				});
			} else {
				$.ui.accordion.animations[options.animated]({
					toShow: toShow,
					toHide: toHide,
					complete: complete,
					down: down,
					autoHeight: options.autoHeight
				});
			}
		} else {
			if ( !options.alwaysOpen && clickedActive ) {
				toShow.toggle();
			} else {
				toHide.hide();
				toShow.show();
			}
			complete(true);
		}
	}
	
	function clickHandler(event) {
		var options = $.data(this, "accordion").options;
		if (options.disabled) {
			return false;
		}
		
		// called only when using activate(false) to close all parts programmatically
		if ( !event.target && !options.alwaysOpen ) {
			options.active.parent().andSelf().toggleClass(options.selectedClass);
			var toHide = options.active.next(),
				data = {
					instance: this,
					options: options,
					newHeader: jQuery([]),
					oldHeader: options.active,
					newContent: jQuery([]),
					oldContent: toHide
				},
				toShow = (options.active = $([]));
			toggle.call(this, toShow, toHide, data );
			return false;
		}
		// get the click target
		var clicked = $(event.target);
		
		// due to the event delegation model, we have to check if one
		// of the parent elements is our actual header, and find that
		if ( clicked.parents(options.header).length ) {
			while ( !clicked.is(options.header) ) {
				clicked = clicked.parent();
			}
		}
		
		var clickedActive = clicked[0] == options.active[0];
		
		// if animations are still active, or the active header is the target, ignore click
		if (options.running || (options.alwaysOpen && clickedActive)) {
			return false;
		}
		if (!clicked.is(options.header)) {
			return;
		}
		
		// switch classes
		options.active.parent().andSelf().toggleClass(options.selectedClass);
		if ( !clickedActive ) {
			clicked.parent().andSelf().addClass(options.selectedClass);
		}
		
		// find elements to show and hide
		var toShow = clicked.next(),
			toHide = options.active.next(),
			//data = [clicked, options.active, toShow, toHide],
			data = {
				instance: this,
				options: options,
				newHeader: clicked,
				oldHeader: options.active,
				newContent: toShow,
				oldContent: toHide
			},
			down = options.headers.index( options.active[0] ) > options.headers.index( clicked[0] );
		
		options.active = clickedActive ? $([]) : clicked;
		toggle.call(this, toShow, toHide, data, clickedActive, down );
	
		return false;
	};
	
	function findActive(headers, selector) {
		return selector != undefined
			? typeof selector == "number"
				? headers.filter(":eq(" + selector + ")")
				: headers.not(headers.not(selector))
			: selector === false
				? $([])
				: headers.filter(":eq(0)");
	}
	
	$.extend($.ui.accordion, {
		defaults: {
			selectedClass: "selected",
			alwaysOpen: true,
			animated: 'slide',
			event: "click",
			header: "a",
			autoHeight: true,
			running: 0,
			navigationFilter: function() {
				return this.href.toLowerCase() == location.href.toLowerCase();
			}
		},
		animations: {
			slide: function(options, additions) {
				options = $.extend({
					easing: "swing",
					duration: 300
				}, options, additions);
				if ( !options.toHide.size() ) {
					options.toShow.animate({height: "show"}, options);
					return;
				}
				var hideHeight = options.toHide.height(),
					showHeight = options.toShow.height(),
					difference = showHeight / hideHeight;
				options.toShow.css({ height: 0, overflow: 'hidden' }).show();
				options.toHide.filter(":hidden").each(options.complete).end().filter(":visible").animate({height:"hide"},{
					step: function(now) {
						var current = (hideHeight - now) * difference;
						if ($.browser.msie || $.browser.opera) {
							current = Math.ceil(current);
						}
						options.toShow.height( current );
					},
					duration: options.duration,
					easing: options.easing,
					complete: function() {
						if ( !options.autoHeight ) {
							options.toShow.css("height", "auto");
						}
						options.complete();
					}
				});
			},
			bounceslide: function(options) {
				this.slide(options, {
					easing: options.down ? "bounceout" : "swing",
					duration: options.down ? 1000 : 200
				});
			},
			easeslide: function(options) {
				this.slide(options, {
					easing: "easeinout",
					duration: 700
				});
			}
		}
	});
	
	// deprecated, use accordion("activate", index) instead
	$.fn.activate = function(index) {
		return this.accordion("activate", index);
	};

})(jQuery);
